This document provides an introduction to Web 2.0 including: - A brief history of the internet from its origins to the emergence of Web 2.0 characterized by user participation through blogs, social media, and user-generated content. - Key aspects of Web 2.0 like its focus on users being able to both read and write/edit content through technologies like wikis and the social aspect of connecting users. - Implications for businesses to authentically engage with online communities and maintain trust through their online brand.